Here is the full list of all 16 弾幕月曜日終章 Playtest achievements.
Played Chapter mode.
Cleared Chapter 1.
Cleared Chapter 2.
Cleared Chapter 3.
Cleared Chapter 4.
Cleared Chapter 5.
Cleared Chapter mode.
Completed all missions in Chapter 1.
Completed all missions in Chapter 2.
Completed all missions in Chapter 3.
Completed all missions in Chapter 4.
Completed all missions in Chapter 5.
Completed all missions in Chapter mode.
Cleared Pre Chapter mode.
Cleared True Chapter mode.
Completed all missions in True Chapter mode.